Patent GB-868413-A (GB)
Title: Improvements in or relating to sliding clasp fasteners
Inventor: EVANS HERBERT
IPC: A44B19/14
Filed: 1957-08-30
Abstract: 868,413. Sliding clasp fasteners. FLEX FASTENERS Ltd. Aug. 20, 1958 [Aug. 30, 1957; Sept. 20, 1957], Nos. 27380/57 and 29638/57. Class 44. A sliding clasp fastener comprises two tapes 1 or similar flexible carriers at least one of which is provided with engageable interlocking members 3 in the shape of closed seamless rings, each interlocking member of the carrier having a coupling element 4 arranged, shaped and adapted to engage a corresponding interlocking member of the other carrier, adjacent interlocking members 3 of the carrier being joined together by bridge pieces 5 in the shape of cylinder segments so that the interlocking members 3 and the bridge pieces 5 constitute a unitary string 2 of the members, the bridge pieces defining the distances between adjacent interlocking members and facilitating the attachment of the string to the carrier. As shown, in which the members for each tape are identical in form, each string is made from a tube, which may be of nylon or other plastic material, by temporarily pressing at least a portion of the tube flat and then punching, cutting or otherwise removing portions of the tube to thereby provide the coupling elements 4 and the bridge pieces 5. The string 2 is attached to the tape 1 by sewing with threads 7, 8 which cross each other at the bridge pieces 5 and the tape edge 6. Alternatively the string 2 may be attached by sewing to a cord or braid, Fig. 6 (not shown) which is subsequently sewn to the tape. In another arrangement, Fig. 8 (not shown), the cord may be moulded into the tube. In a further arrangement Fig. 9 (not shown) the tape is provided with a beaded edge to which the string 2 is sewn. According to Fig. 10 (not shown) the string is nested and secured between two branches at the tape edge. In a modification, the edge of the tape is formed with three branches and the string is nested and secured between the outer branches. In a modification of the Fig. 10 arrangement, Fig. 12 (not shown) the tape is provided with beadings at the junction of the branches. In the arrangement according to Fig. 13 (not shown) the string 2 is passed through openings of a ladderlike tape which is then bent about the bridge-pieces of the string and the overlying parts of the tape secured by stitching or gluing, In another construction, Fig. 14 (not shown), the edge of the tape is applied between a pair of ribs or against a single rib provided on the string 2. In a modified method for making a pair of strings, a twin tube, Figs. 15 and 18, is pressed flat and the coupling elements 4 formed as in the previous arrangements, the centre part 103 of the tube being subsequently cut longitudinally to produce the two strings. In a modification, Fig 20 (not shown), the coupling elements are formed at the centre part of the twin tube which is subsequently cut to produce the two strings. The coupling elements of one string may be displaced longitudinally in relation to the elements of the other string, Fig. 21 (not shown). A device for making the string 2 comprises a base 301, Fig. 22, carrying a guide 302 for a tube 304 of the material of the string. The tube is fed through the device in steps by a toothed wheel 321 which is connected through a linkage 323 to an actuator 305 reciprocable towards and away from the tube 304. While the tube 304 is at rest the actuator 305 moves towards the base 301 and first depresses a flattening shoe 306 on to the tube to flatten the tube and upon continued movement thereafter moves a punch 311 on to the tube to punch out a portion thereof while still flat. During this time slides 314 approach each other and exert pressure on the previously punched wall of the tube to assist the tube in substantially regaining its original shape. Subsequently the actuator recedes from the base and the wheel 321 moves the tube forward one step in readiness for the next flattening and punching operation by the actuator 305.